Senior Fullstack Software Engineer – Ruby/Typescript

Join 1KOMMA5°, a global energy technology company building the next-generation renewable energy system. We are seeking a Senior Fullstack Software Engineer with expertise in Ruby/Typescript to help transform the installation and management of renewable technologies worldwide. Your Role: Develop and maintain core Rails applications with focus on code quality and long-term stability. Lead technical implementation of complex projects using ShapeUp methodology in 6-week cycles. Build pragmatic integrations between Rails monolith and TypeScript/GCP services. Proactively improve developer experience through tooling and CI/CD optimization. Drive high-quality async collaboration through clear documentation and code reviews. Required Skills: - Proven experience writing maintainable, testable code with Rails and major backend/full-stack technologies - Experience designing and maintaining RESTful APIs - Performance measurement and optimization expertise - Agile, result-oriented mindset with strong team support capabilities - Excellent English proficiency; German is a plus - Residency in Germany required Technologies: Ruby/Rails, TypeScript/JavaScript, Event Sourcing, Postgres, Firestore, Datadog, GCP (Pub/Sub, Cloud Functions), Auth0, OpenAPI. Benefits: Work remotely across Germany with offices in Hamburg, Berlin, and Munich. Join an international, dynamic team accelerating the energy transition with direct climate impact. Access to EGYM Wellpass benefits, job bike leasing, and work-life balance initiatives. Opportunity to join one of Europe's most thriving scaleups. Company: 1KOMMA5° operates in 80+ locations worldwide with 3,000+ employees, building intelligent renewable energy systems for 1.5 million households by 2030.